The devices described herein came about because of a need to enable and simplify the placement of a product marketed under the trademark PerioChip.RTM. on anterior teeth, and especially on the mesial and distal surfaces of posterior teeth. The PerioChip product (made by Perio Products Ltd., in Israel, and marketed in the United States by Astra Pharmaceuticals, LP) is a small and thin chip of medication (chlorhexidine gluconate) which can be inserted in periodontal pockets between the teeth and surrounding gingival tissue. The chip is approximately square with a slightly rounded leading edge for ease of insertion, and typically measures about 4 mm.times.5 mm.times.350 .mu.m. The chip is relatively easy to insert in accessible periodontal pockets of the anterior teeth, but difficult to grip securely for precise and gentle placement in the pockets of posterior teeth.
Described below are several different embodiments of a chip gripping and placement tool which is essentially a modification of a standard dental cotton pliers (the term "pliers" is conventional in dentistry, though the tool is nonpivoted, and can also be called a tweezers or forceps). Though referred to herein as a "dental pliers," the invention is not limited to dental applications, and is useful to grip and place a variety of small objects.
For placement on all anterior surfaces and the lingual and buccal of posterior teeth, the non-serrated or serrated tips, Teflon-coated or non Teflon-coated tips of the cotton pliers have been angled inward to an angle of 70 degrees, while the tips themselves have been made thinner while maintaining their width. Handles of the pliers have been altered by adding a small fulcrum point to one handle adjacent the bend of the tips, and a small movement-limiting screw approximately one-third of the way up the handles. These four modifications allow a closed or clamped position of the tips in the resting or relaxed mode, and an open mode with the tips spaced apart in the range of 1 to 3 millimeters (easily expanded to 6 or 7 millimeters should wider spacing be desired) with the tool handles squeezed together. Gentle pressure is applied to the handles of the placement pliers thus opening the tips to allow the practitioner to pick up the chip, release the handles thereby locking the chip in place without fear of dropping it before it reaches the mouth, placing the chip in a desired location of a periodontal pocket, and again pressing the handles together to release the chip and remove the placement pliers.
For easier placement of the chlorhexidine chip on the mesial and distal surfaces of the posterior teeth, and labial and lingual surfaces of the anterior teeth, the cotton pliers are altered by turning the serrated or non-serrated, Teflon-coated or Teflon-free tips about 90 degrees from their original position, then downward to about a 70-degree angle, while the tips themselves have been made thinner while maintaining their width. The handles have been altered by adding a small fulcrum point to an inner surface of one of the tips adjacent the bend of the tips, and a small screw approximately one-third of the way up the handles. These four modifications allow a closed position at the tips in the resting mode, and an open position of 1-3 mm in the open mode. The application of the chip would proceed as described for the pliers designed for the anterior surfaces, and the posterior buccal or lingual surfaces.
Note that from the alterations described, while the handles of the anterior, buccal and lingual placement pliers would maintain their original position of vertical placement, one side by side of the other, the handles of the posterior mesial and distal placement pliers would be in a horizontal position, one on top of the other.